| 摘要 |
An encoder has the capability of outputting a stable displacement signal with small distortion. The encoder includes a first scale and a second scale. The first or second scale has a scale pattern in which pattern elements are arranged in such a manner that the spacings between adjacent pattern elements are not constant but vary in phase relative to the reference phase of a reference pattern element by amounts of P/(2xL), P/(2xm), P/(2xn), P/(2xo), . . . (L, m, n, o, . . . are positive integers, P is the mean pattern period) and by amounts of combinations of sums of these values.
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